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<div class="titlepage"><div><div><h4 class="title">
<a name="geometry.reference.concepts.concept_segment"></a><a class="link" href="concept_segment.html" title="Segment Concept">Segment
        Concept</a>
</h4></div></div></div>
<h6>
<a name="geometry.reference.concepts.concept_segment.h0"></a>
          <span class="phrase"><a name="geometry.reference.concepts.concept_segment.description"></a></span><a class="link" href="concept_segment.html#geometry.reference.concepts.concept_segment.description">Description</a>
        </h6>
<p>
          The Segment Concept describes the requirements for a segment type. All
          algorithms in Boost.Geometry will check any geometry arguments against
          the concept requirements.
        </p>
<h6>
<a name="geometry.reference.concepts.concept_segment.h1"></a>
          <span class="phrase"><a name="geometry.reference.concepts.concept_segment.concept_definition"></a></span><a class="link" href="concept_segment.html#geometry.reference.concepts.concept_segment.concept_definition">Concept
          Definition</a>
        </h6>
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
              there must be a specialization of <code class="computeroutput"><span class="identifier">traits</span><span class="special">::</span><span class="identifier">tag</span></code>
              defining <code class="computeroutput"><span class="identifier">segment_tag</span></code>
              as type
            </li>
<li class="listitem">
              there must be a specialization of <code class="computeroutput"><span class="identifier">traits</span><span class="special">::</span><span class="identifier">point_type</span></code>
              to define the underlying point type (even if it does not consist of
              points, it should define this type, to indicate the points it can work
              with)
            </li>
<li class="listitem">
              there must be a specialization of <code class="computeroutput"><span class="identifier">traits</span><span class="special">::</span><span class="identifier">indexed_access</span></code>,
              per index and per dimension, with two functions:
              <div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: circle; ">
<li class="listitem">
                    <code class="computeroutput"><span class="identifier">get</span></code> to get a
                    coordinate value
                  </li>
<li class="listitem">
                    <code class="computeroutput"><span class="identifier">set</span></code> to set a
                    coordinate value (this one is not checked for ConstSegment)
                  </li>
</ul></div>
            </li>
</ul></div>
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<th align="left">Note</th>
</tr>
<tr><td align="left" valign="top"><p>
            The segment concept is similar to the box concept, defining using another
            tag. However, the box concept assumes the index as <code class="computeroutput"><span class="identifier">min_corner</span></code>,
            <code class="computeroutput"><span class="identifier">max_corner</span></code>, while for
            the segment concept, there is no assumption.
          </p></td></tr>
</table></div>
<h6>
<a name="geometry.reference.concepts.concept_segment.h2"></a>
          <span class="phrase"><a name="geometry.reference.concepts.concept_segment.available_models"></a></span><a class="link" href="concept_segment.html#geometry.reference.concepts.concept_segment.available_models">Available
          Models</a>
        </h6>
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
              <a class="link" href="../models/model_segment.html" title="model::segment">model::segment</a>
            </li>
<li class="listitem">
              <a class="link" href="../models/model_referring_segment.html" title="model::referring_segment">referring
              segment</a>
            </li>
</ul></div>
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<td align="right"><div class="copyright-footer">Copyright © 2009-2021 Barend Gehrels,
      Bruno Lalande, Mateusz Loskot, Adam Wulkiewicz, Oracle and/or its affiliates<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
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